Research On Digital Micro Jetting Technology And Its Application In Micro Mixing For Micro Fluidic System

Micro fluidic system is an important branch of micro systems. And micro jetting and micro mixing technology are the important research contents of the micro fluidic system. There are a lot of realization methods for micro jetting and micro mixing, but most of them have bottlenecks such as special properties request for fluid, difficulty of fabrication of the micro components and so on. Therefore problems in method for driving microfluid, micro jetting and mixing technology without special fluid properties request, designing and fabrication of the micro components and application researchs of micro jetting and mixing technology should be well solved.There are some creative theories in the digitalization of micro fluidic technology, which exploits the field of the digital matter transportation, equaled with the informationization, digital energy transmission and solid movement. Considering the aspects of theory and experiment research on micro fluidic and designing and fabrication of the basic micro components, the research achievements on the theory of micro fluidic driving, digital micro jetting technology, designing and fabrication of the micro jet-mixer and confirmed and applied experiments of digital micro jet-mixer are presented as follow base on the digitalization of micro fluidic technology.A novel micro fluidic driving technique is proposed on the friction coupling effect between the micro fluidic boundary layer and solid wall of the microchannel. Dynamic aspects of the micro flow in cylindrical microchannels are analysed. The validity of the presented principle is verified by experiments. A new structure of microchannel is designed and the principle and impact factors of micro jetting are analyzed.Digital micro jetting has been realized by micro jetting experiment. The impact factors of micro jetting were summarized, and the correlative parameters of micro jetting were measured. The digital micro jetting has the characteristic of high stability, uniformity, resolution and real time control. The kinds of the fluid materials that can be injected include conventional liquids as well as solid powders, pastes, and other substances of similar characteristics.Two types of micromixer are designed by micro jetting technology. One is Y-type and other is co- axial. The micro jet-mixer is fabricated by fitting glass microchannels together without micro moving parts. These glass microchannels are produced by microchannel puller dispense with complicated microfabrication technology, hence greatly simplifying the structure and reducing the cost. The performance of the mixer is verified by the different experiments. Digital micro mixing- reaction has been realized. The kinds of the fluid materials that can be mixed include conventional liquids as well as solid powders, pastes, and so on. By changing the driving parameters, the mixing effect can be improved effectively.The application of digital micro jet-mixer in micro manufacturing is researched. A new method of microcapsule molding by digital micro jet-mixer is proposed. The microcapsule with different kinds of core materials can be modeled by co-axial type and Y- combined co-axial micro jet-mixer at normal temperature and pressure. The microcapsule has regular appearance and even size. The size and conformation of microcapsules can be controlled through changing driving parameters. By Y- type micro jet-mixer and technology of chemical deposition of silver, micron scale silver lines were obtained with fine structure, smoothness of edge and width. Micro component of silver in three dimensions was manufactured by superposition of the composite coat.